A. Field of the Invention
The field of the present invention relates generally to emergency flotation devices adapted to assist in the rescue of persons in bodies of water. More particularly, the present invention relates to such emergency flotation devices that are configured to be easily throwable and which automatically inflate upon contact with the body of water. Even more particularly the present invention relates to such emergency flotation devices which have a generally baton-shaped body member for throwing and a flotation component configured to support a person in the body of water.
B. Background
Accidental drowning is an unfortunate risk of most recreational or occupational activities, such as boating, swimming and the like, that take place around or in bodies of water, including lakes, rivers, canals, and oceans. Accidental drowning is also a substantial risk during natural disasters, such as floods, and transportation accidents over a body of water, such as airplane crashes, sinking boats and the like. Generally, all such drownings begin with a person falling or thrown into the body of water and then being unable to swim or otherwise make it to safety, which may be the shore or a structure or other safe location (i.e., a raft or boat) in the water, due to their inability to swim, swim the required distance or swim in the water conditions (i.e., cold, choppy water, etc.). For many drowning events, there is some period of time between when a person falls or is thrown into the water and when the person drowns in which help could be provided to him or her by others that would prevent the drowning. Typically, this help is in the form of providing the person in the water a personal flotation device that is suitable for safely supporting the person in the water until a more permanent rescue can be effectuated (i.e., pulling the person out of the water or being picked up by boat or helicopter). Common types of personal flotation devices, which are configured, adapted and/or intended for use by a single person as opposed to a group of persons (i.e., which require a large life raft or the like), include life jackets or vests, cushions, rings and horseshoe configured devices. The purpose of a personal flotation device is to keep a person afloat until he or she is rescued. It is generally not a purpose of such devices to provide a water craft for sustained use in and/or movement through the water.
While such devices generally are well suited for providing a person in the water with a way to keep afloat without tiring (i.e., from treading water) until he or she is rescued, they do have some substantial drawbacks that limit their effectiveness in many situations. Life jackets must be on the person before he or she falls into the water and becomes a potential drowning victim, or he or she must be able to put the life jacket on while in the water (i.e., while treading water or the like). Unfortunately, due to the circumstances of the entry into the water or the water conditions, the person may be unable to put the life jacket on or put it on in a manner such that it stays on. Obviously, a person who is seriously injured or otherwise unable to manipulate a life jacket while in the water is not able to take advantage of being provided with the life jacket. In addition, most life jackets, cushions, rings or horseshoe devices are difficult to throw very far or with any accuracy. As such, if a person falls into the water and someone is able to throw a typical personal flotation device to them, it is not uncommon for the person throwing the device to not be able to throw it very far or with any accuracy. As known to those skilled in the art, including rescue personnel and life guards, there is a certain amount of skill involved, which typically takes training to acquire, in order to effectively throw a personal flotation device to a drowning person. As such, these devices often do little to assist the person who is more than 50 feet or so from shore, structure, vessel or other safe location.
For storage and delivery (i.e., throwing) purposes, many personal flotation devices are stored without air inside them, which requires the rescuer or the person in the water to fill the device with air before it can be effectively utilized. As discussed above, often it can be very difficult for the person in the water to place the required quantity of air, such as by blowing, into the personal flotation device and many rescuers may not have or take the time to fill it before throwing. A number of personal flotation devices were developed that allow the person in the water to quickly fill the device with the amount of air necessary for the device to be effectively utilized. Generally, these personal flotation devices include a source of pressurized gas, a bladder that is suitable for receiving the pressurized gas and supporting the person in the water and some type of switch or other activating mechanism for initiating the flow of pressurized gas from the source to the bladder. An example of such a device is shown in U.S. Pat. No. 3,828,381 to Prager and an example of a manual inflation manifold is disclosed in U.S. Pat. No. 3,809,288 to Mackal. The source of pressurized gas is typically a canister or other container having carbon dioxide or other non-flammable and non-toxic gas that is under sufficient pressure to rapidly fill the bladder to provide a support for the person in the water while he or she waits for a more permanent rescue. Although the activating mechanisms used with most such devices generally appear to be easy to operate when viewed safely on shore or other places where there is no risk of drowning and no water conditions (i.e., waves, rain, etc.) to deal with, under real potentially drowning conditions, the person in the water may have difficulty in operating the activating mechanism so as to fill the bladder with air.
To overcome the problems associated with personal flotation devices that require manual operation of an activating mechanism, various improved personal flotation devices have been developed that include automatic activating mechanisms or inflators that are configured to automatically transfer gas from the source of pressurized gas to the bladder upon exposure to water. These devices typically comprise a gas cartridge having a pierceable or frangible seal and a spring loaded piercing pin that is driven into the seal to cause compressed gas to flow from the canister to a manifold that pneumatically connects to the bladder to be inflated. The typical mechanism for driving the piercing pin is a cam that is driven by a water activated trigger assembly that includes either a water destructible or dissolvable element or cartridge that, in the set position before exposure to the water, retains an actuator pin in a cocked or ready position in alignment with the piercing pin. Examples of some automatic inflators which utilize water destructible or dissolvable elements to trigger the piercing pin are set forth in various patents to Mackal, et al. (i.e., U.S. Pat. Nos. 6,705,488; 6,589,087; 4,627,823; 4,223,805; 4,267,944; and 4,260,075), U.S. Pat. No. 2,894,658 to Spidy, U.S. Pat. No. 3,526,339 to Bernhardt, et al. and U.S. Pat. No. 3,997,079 to Niemann. When these trigger assemblies are exposed to water, the dissolvable elements dissolve to release the piercing pin and fracture the seal of the cylinder to release the pressurized gas into the inflatable bladder portion of the flotation device. As noted in U.S. Pat. No. 4,627,823 to Mackal, a major disadvantage of some of these prior art devices was their tendency to self-actuate, causing premature and unintentional inflation of the inflatable bladder during storage, particularly in the humid environments typically found on ships or near bodies of water. The device of this Mackal patent (No. 4,627,823) is configured to be housed in a bracket assembly for attachment to a stationary object such that when the device is released from the bracket, the actuator is mechanically cocked to arm the device for use.
An alternative to the water destructible or dissolvable elements utilized in the personal flotation devices described above are devices which utilize electrically operated actuation assemblies, such as those described in U.S. Pat. No. 4,094,028 to Fujiyama, et al., U.S. Pat. No. 4,768,128 to Jankowiak, et al. and U.S. Pat. No. 5,400,922 to Weinheimer, et al. The patent to Fujiyama describes an automatic inflating buoy that has a gas generating composition, an electric ignition device to ignite the composition and a cooling agent for cooling the gas generated by the burning or decomposition of the gas before it enters the inflatable bag. An electric cell or battery supplies the current to the electric ignition device when contacted by water. The Fujiyama patent notes the problems with utilizing pierceable gas cylinders to fill the buoy in colder temperatures, namely that the discharge speed is slow, making it difficult to fill the buoy. The patent to Jankowiak describes a water activated pressurized gas release device configured to inflate personal flotation equipment when immersed in water. The actuation assembly has a battery operated circuit that operates by completing the circuit when the device is immersed in water to ignite an explosive primer so as to drive the piercing pin into the pierceable closure on the container holding the pressurized gas. A device made according to this patent is commercially available as the “Deck Crew” automatic inflation device from Conax Florida Corporation out of St. Petersburg, Fla. The patent to Weinheimer describes a automatic inflator for personal flotation devices that utilizes a battery-powered, water-sensing electrical circuit that supplies power to a fusible link actuator assembly upon immersion of the device in water. Upon immersion in water, the electrical circuit fuses a fuse bolt to allow a spring to force a slidable link forward within the actuator so as to force the firing lever to move upward and forcibly urge the firing pin to pierce the frangible seal of the gas cartridge.
One significant disadvantage of the prior art automatic inflating personal flotation devices is their inability to be easily deployed by throwing during an emergency situation, such as a potential drowning. In general, the prior art devices are too bulky and/or weight too much to be easily and effectively thrown any substantial distance by the typical person. As with the early and still most common personal flotation devices, the standard, non-inflatable rings and horseshoe devices, the prior art automatic inflating personal flotation devices are not easy to throw more than a relatively short distance, particularly with any accuracy. Another significant disadvantage of many of the prior art automatic inflating personal flotation devices is that they can be difficult to conveniently and safely store while waiting use. Another disadvantage of some prior art devices having enclosed housings is the positioning of the manual “back-up” actuator inside the enclosed cartridge, which requires the cartridge to open before the back-up can be utilized.
What is needed, therefore, is an improved automatic inflatable personal flotation device that is easier for the average person, particularly untrained persons, to throw an effective distance with accuracy. The preferred automatic inflatable personal flotation device will automatically inflate upon contact with water and, in case of malfunction of the automatic actuator, be easy for the potentially drowning person to manually actuate. The preferred automatic inflatable personal flotation device will be made out of materials that are generally lightweight, durable, suitable for use in outdoor environments and be configured for use with either an electrically operated actuator or an actuator using a destructible or dissolvable element to automatically actuate a piercing pin capable of piercing a frangible seal on a pressurized gas cartridge. The preferred automatic inflatable personal flotation device of the present invention will utilize a cylinder of compressed gas but be configured to reduce the known negative effects of cold and hot temperatures on such cylinders and be configured to protect the cylinder from damage due to unintended contact with another surface. Ideally, the preferred automatic inflatable personal flotation device should be relatively inexpensive to manufacture and adaptable for a variety of different emergency uses.